Certificate of correction



March'3, 1964 w. B. WHIPPO 3,123,346

HARMONIC INERTIA SNUBBER Filed Nov. 30. 1960 IN V EN TOR. M17??? 8.1449/1 0 United States Patent 3,123,346 HARMQNIC ENERTIA SNUBBER WalterB. Whippo, Cayuta, N.Y., assignor to Sperry Rand Corporation, New York,N.Y., a corporation of Delaware Filed Nov. 30, 1960, er. No. 72,531 13Claims. (tCl. 2d7-1) This invention relates to motion checking devicesand in particular to means for providing harmonic deceleration for apart moving to a stop, so that the shock and noise normally accompanyingstopping of a moving part will be greatly reduced and to a degree notachieved by present stopping devices such as pins, springs, bumpers,dashpots or the like.

A particular object of the invention is to provide a harmonic inertiasnubber, the success of which depends on the embodiment of fundamentallaws, namely (1) the energy of a system equals the mass times thevelocity squared/ 2; (2) the presence of gravity and inertia in anymass; and (3) the trigonometric functions of a circle; resulting in adevice that is simple in structure, and reliable and predictable inoperation.

A further object of the invention is to provide a ring and pincombination in which the effectiveness of the de vice can be controlledby the density of the ring material; the width, thickness and diameterof the ring, and the ratio of the diameter or" the ring to the diameterof the pin.

()ther objects and structural details of the invention will be apparentfrom the following description when read in connection with theaccompanying drawing, wherein:

FTGURE 1 is a side view of one end of a member to be stopped showing thelatter in contact with a ring freely suspended from a pin;

FIGURE 2 is a view similar to FIGURE 1 showing the movement of the ringwhich shifts the center of gravity thereof from beneath the pin;

FIGURE 3 is a view similar to FIGURE 2 showing the shift of gravity tomaximum extent and the limit movement of the part to be broug t to astop;

FIGURE 4 is a view showing the parts in vertical position andcounterbalancing means applied to the ring which is arranged to swingvertically to arrest a vertically moving part to be stopped; and

FIGURE 5 is a view similar to FIGURE 4 showing a modified form of ringcounterbalancing means that operates to yieldably maintain the ring in ahorizontal position.

One example to which my invention may be put, to illustrate thepractical use thereof, would be in a business machine in which it ishighly desirable to stop a platen carriage movement at the end of itsreturn travel with a minimum of noise and rebound. To this end, tilindicates the moving part of any member that is to be brought to a stopwhile moving in a horizontal path and having an end portion 11 that isat least as wide as half the diameter of a stop ring 12 which issuspended freely from a pin 13 that coacts with the ring 12 in arrestingthe movement of the part ll).

The ring 12 can be made from any material and will conform to the lawsabove mentioned, but I prefer the use of a ring made of nylon which ishung loosely on the pin 13 and at rest assumes a position in a verticalplane.

Tee

The part 10 whose motion is to be stopped moves toward the pin and atits leading vertical end edge 11 contacts the outer surface of the ringfirst. This contact point is degrees away from the point Where the ring12 contacts the pin from which it hangs. The center of gravity of thering is normally directly below the pin, but with cont nued motion ofthe part It), to be stopped, towards the pin, the ring 12 is now movedin the same direction as the moving part. As the part 10 moves closer tothe pin 13 the center of gravity of the ring designated as at 14 swingsin an are about the pin until it has moved through 90 degrees ofrevolution, and is at the same level as the pin 13, and the moving partill is stopped.

By moving the center of gravity of the ring from beneath the pin, workenergy will be extracted from the moving part, and the rate at whichthis energy is extracted increases as the sine function of the movementof the center of gravity 14 of the ring about the pin. The effect ofthis transfer of energy is to harmonically reduce the energy of themoving part ill to zero.

The result of this harmonic reduction of the energy of the moving partis that it approaches its final stopping point with continuallydecreasing energy and arrives at a dead stop with theoretically notendency to bounce, vibrate or produce noise, since theoretically all ofits energy has been extracted by the motion imparted to the ring. Inpractice due to efficiency losses, the device will not reach perfection,but the results are dramatically superior to existing snubbers, bumpersand stops, since none of these achieve the cycloidal reduction ofmomentum necessary to quietness and smooth operation. An additionalfeature is that a point on the ring precesses around the ring with eachoperation of the snubber, presenting a new surface after each cycle.This will tremendously increase the durability of the snubber and thereliability of its dimensions over existing snubbers. This device maywork in planes other than the vertical, by applying a spring or acounter balance to the device as a substitute for gravity. A springwould produce a variation of the harmonic reduction in energy since itwould not apply a constant force throughout its travel, and asillustrated in FIGURE 4, one form of spring 16 is used which may besecured to the ring 15 in horizontal alignment with the pin 17 as at 18and be held in an adjusting device 19 for varying the tension of thespring. The moving part 17A, provided with a flat top edge 18A, which issubstantially as Wide as half the diameter of the ring, is in alignmentwith the pin 17 and engages the outside surface of the ring 15initially, at a point vertically aligned with the center of gravitydesignated here as at 20.

In the form illustrated in FIGURE 5 the pin 21 has secured to an innerflattened side thereof the fiat portion 22 of a leaf spring having legs23 which terminate in rounded ends 2 4 for engagement with the innerperiphery of the ring 25. The spring provides the flexible le s 23 whichyieldably hold the ring 25 against vertical movement but allow the ringto be pushed by the moving part 26 to alter the position of its centerof gravity 27 in accordance with the outline showing in FIGURE 5. Eachleg 23 is independently flexible and the lower leg will yield as thering moves away from the upper leg. The spring acts as a self restoringagent for the ring after the moving part 26 has been retracted.

In the form of the invention shown in FIGURE 4, the

above disclosed and it is therefore desired that only such limitationssna'l be imposed on the appended claims as are stated thc in, orrequired by the prior art.

What i claim as new and desire to secure by Letters Patent is:

1. A devi e for arresting the motion of a movin r emher, compri an n armeans, and a member stationary with respect to said moving membercontacting said annular means along a portion of its inner annularsurface to support said annular n ns for swinging movement underinfluence of said mov ng member to hermonically decelerate the movementof said moving member.

2. A device for arresting the motion of a moving part, comprisingannular means, and a support member stationary With respect to saidmoving member engaging said annular means along a p ion of the innerannular surface thereof to support said aimular means for swingingmovement to provide harmonic dccel ration of said moving part, saidannular at the end of its swinging movement coacting with said supportmember for providing a stop for said movirg 3. In a device for arrestingthe movement of a part having an edge portion, fixed pin means in thepath of movement of said edge portion, and ring means supported at oneportion the eof by said pin means and arranged to be swung by s d edgeportion as the latter moves toward said pin m ns, the center of gravityof the ring means during swinging movement being displaced [from a"first position through an arc of substantially ninety degrees toprovide harmonic deceleration of said moving part until said means andoin means arrest the movement of said part.

4. in a device for arresting the movement of a part having a straightedge portion, fixed pin means in the path of movement of said edgeportion, ring means supported at one portion thereof by said pin meansand arranged to be swung by said edge portion as the latter moves towardsaid pin means, the center of gravity of the ring means during 'vingingmovement thereof being displaced from an i 1 position through an arc ofsubstantially ninety degrees to provide harmonic deceleration of saidmoving part, and tension means associated with said ring means foryieldably resisting movement of said ring means.

5. in a device for arresting the overnent of a part having a straightedge portion, fixed pin means in the path of movement of edge portion,ring means so,- P-Oft6d at one portion the of by said pin means andarranged to be swr g t y said edge portion as he latter moves towardsaid pin means, the center of vity of the ring means during displacedfrom an n ion through an arc of substantially ninety degrees to provideharmonic deceleration of said moving part, tension means associated withsaid ring means for yieldably resisting movement of sa d means, d foradjusting tension to increase the resistance to movement of said ringmeans.

6. In a device for arresting the movement of a part having ve-rt ""1 ed"portion, fixed pin means in the path of said edge ltion, and ring meanshaving its center of gravity below said pin means and being suspendedfrom said pin means in the path of said edge 11ortion, said ring meansbeing engaged and sv e by said edge portion as said part moves closer toszu t means the center of gravity of said ring means swinging in an swining movement thereof being arc of substantially ninety degrees about thepin m ans and to horizontal alignment with said pin means to provideharmonic deceleration of said moving part until the ring and pin meanscoact to stop said moving part.

7. In a device for arresting the movement of a part having a fiat edge,fixed pin means in the path of said edge, and ring means having an innerring surface and disposed With a portion of said inner ring surf-ace incontact with said pin means to be supported by said pin means in thepath or" said edge for engagement thereby, said ring means ha ingsubstantially a precessional movement along said edge and providingharmonic deceleration of said moving part as said edge approaches saidpin means and until said edge engages that portion of said ring meansbetween said pin means and the said edge to provide a stop.

8. In a device for arresting the movement of a part having a fiat edge,fixed pin means in the path of s edge, ring means having an inner ringsurface and disposed with a portion of said inner ring surfs e in engagment with said pin means to be supported by said pin means substantiallyin the path or" said edge for engagement thereby, said ring means havingsubstart' precessiona l movement along said edge and pro a. harmonicdeceleration of said moving part said edge approaches said pin means anduntil said edge engages that port-ion of said ring between said pinmeans and said edge to provide a stop, and yieldable means associatedwith said ring means for yieldably resisting movement of said ringmeans.

9. In a device for arresting the movement of a part having a flat edge,fixed pin means in the path of said edge, ring means having an innerring surface and disposed With a portion of said inner ring surface inengagement with said pin means sugaported on said pin means in the pathof said edge for engagement thereby, said ring means havingsubstantially a precessionai movement along said edge and providingharmonic deceleration of said moving part as said edge approaches saidpin means and until said edge engages that portion of said ring meansbetween said pin means and said edge to provide a stop yieldable meansassociated with said ring means for yieldably resisting movement of saidring means, and means for adjusting said yieldable means to increase theresistance to movement of said ring means.

10. In a device as set forth in claim 8 in whi h said yieldable meansincludes a spring With one end thereof fixedly positioned and the otherend thereof secured to said ring means at a point diametrically oppositesaid pin means to vary the harmonic decelerating action of said ringmeans in swinging movement.

11. A motion arresting mechanism of the class described, comprising amoving member movable in a predetcrmlned path, a support memberstationary With respect to said moving member, and a movable mass havingformed therein an aperture defined by a Wall and adapted to be mountedon said support member with a portion of said wall in contact With anortion of said support member and in the path of movement of saidmoving member for engagement by the latter to hanmcrdoally decelerateand arrest movement of said moving member, said mass being mounted toprovide a center of gravity traversing an arouate path in arrestingmotion of said moving member.

12. The motion arresting mechanism of claim 11 which includes yieldablemeans coacting with said movable mass and adapted to oppose movement ofsaid movable mass by said moving member.

13. in a device for arresting the movement of a part having a flat edge,fixed pin means in the path of said edge, ring means supported on saidpin means and substantially in the path of said edge for engagementthereby, said ring means having substantially a precessional movementalong said edge and prov ding harmonic deceleration of said moving partas said edge approaches 5 said pin means and until said edge engagesthat portion of said ring means between said pin means and said edge toprovide a stop, and yieidable means associated with said ring means foryie-ldably resisting movement of said ring means, said yieldab le meansincluding a leaf spring with the ier surface of saidfa-enu-i---eta0ishrdlu E'I'AO providing diverging leg portions for yieldable engagementwith the inner suriace of said ring means, and

6 means for securing said spring to one side of said pin means.

References Cited in the file of this patent UNITED STATES PATENTS684,997 Matheson Oct. 22, 1901 2,195,041 Von Schlippe Mar. 26, 19402,306,877 Gould Dec. 29, 1942 2,953,076 Leuschke et a1 Sept. 20, 1960UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,123,346 March 3; 1964 Walter B, Whippo It is hereby certified thaterror appears in the above numbered patent requiring correction and thatthe said Letters Patent should read as corrected below.

Column 5, line 6, strike out "with the ier surface of saidfa-enuietaoishrdlu ETAO'H.

Signed and sealed this 7th day of July 1964,

(SEAL) Attest:

ERNEST W; SWIDER A ifisfirig Officer EDWARD J. BRENNER Commissioner ofPatents

1. A DEVICE FOR ARRESTING THE MOTION OF A MOVING MEMBER, COMPRISINGANNULAR MEANS, AND A MEMBER STATIONARY WITH RESPECT TO SAID MOVINGMEMBER CONTACTING SAID ANNULAR MEANS ALONG A PORTION OF ITS INNERANNULAR SURFACE TO SUPPORT SAID ANNULAR MEANS FOR SWINGING MOVEMENTUNDER INFLUENCE OF SAID MOVING MEMBER TO HARMONICALLY DECELERATE THEMOVEMENT OF SAID MOVING MEMBER.